/*
 * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#include <arch.h>
#include <arch_helpers.h>
#include <assert.h>
#include <debug.h>
#include <gic_common.h>
#include "../common/gic_common_private.h"
#include "gicv2_private.h"

/*
 * Accessor to read the GIC Distributor ITARGETSR corresponding to the
 * interrupt `id`, 4 interrupt IDs at a time.
 */
unsigned int gicd_read_itargetsr(uintptr_t base, unsigned int id)
{
    unsigned n = id >> ITARGETSR_SHIFT;
    return mmio_read_32(base + GICD_ITARGETSR + (n << 2));
}

/*
 * Accessor to read the GIC Distributor CPENDSGIR corresponding to the
 * interrupt `id`, 4 interrupt IDs at a time.
 */
unsigned int gicd_read_cpendsgir(uintptr_t base, unsigned int id)
{
    unsigned n = id >> CPENDSGIR_SHIFT;
    return mmio_read_32(base + GICD_CPENDSGIR + (n << 2));
}

/*
 * Accessor to read the GIC Distributor SPENDSGIR corresponding to the
 * interrupt `id`, 4 interrupt IDs at a time.
 */
unsigned int gicd_read_spendsgir(uintptr_t base, unsigned int id)
{
    unsigned n = id >> SPENDSGIR_SHIFT;
    return mmio_read_32(base + GICD_SPENDSGIR + (n << 2));
}

/*
 * Accessor to write the GIC Distributor ITARGETSR corresponding to the
 * interrupt `id`, 4 interrupt IDs at a time.
 */
void gicd_write_itargetsr(uintptr_t base, unsigned int id, unsigned int val)
{
    unsigned n = id >> ITARGETSR_SHIFT;
    mmio_write_32(base + GICD_ITARGETSR + (n << 2), val);
}

/*
 * Accessor to write the GIC Distributor CPENDSGIR corresponding to the
 * interrupt `id`, 4 interrupt IDs at a time.
 */
void gicd_write_cpendsgir(uintptr_t base, unsigned int id, unsigned int val)
{
    unsigned n = id >> CPENDSGIR_SHIFT;
    mmio_write_32(base + GICD_CPENDSGIR + (n << 2), val);
}

/*
 * Accessor to write the GIC Distributor SPENDSGIR corresponding to the
 * interrupt `id`, 4 interrupt IDs at a time.
 */
void gicd_write_spendsgir(uintptr_t base, unsigned int id, unsigned int val)
{
    unsigned n = id >> SPENDSGIR_SHIFT;
    mmio_write_32(base + GICD_SPENDSGIR + (n << 2), val);
}

/*
 * Accessor to write the GIC Distributor ITARGETSR corresponding to the
 * interrupt `id`.
 */
void gicd_set_itargetsr(uintptr_t base, unsigned int id, unsigned int target)
{
    mmio_write_8(base + GICD_ITARGETSR + id, target & GIC_TARGET_CPU_MASK);
}

/*******************************************************************************
 * Get the current CPU bit mask from GICD_ITARGETSR0
 ******************************************************************************/
unsigned int gicv2_get_cpuif_id(uintptr_t base)
{
    unsigned int val;

    val = gicd_read_itargetsr(base, 0);
    return val & GIC_TARGET_CPU_MASK;
}

/*******************************************************************************
 * Helper function to configure the default attributes of SPIs.
 ******************************************************************************/
void gicv2_spis_configure_defaults(uintptr_t gicd_base)
{
    unsigned int index, num_ints;

    num_ints = gicd_read_typer(gicd_base);
    num_ints &= TYPER_IT_LINES_NO_MASK;
    num_ints = (num_ints + 1) << 5;

    /*
     * Treat all SPIs as G1NS by default. The number of interrupts is
     * calculated as 32 * (IT_LINES + 1). We do 32 at a time.
     */
    for (index = MIN_SPI_ID; index < num_ints; index += 32)
        gicd_write_igroupr(gicd_base, index, ~0U);

    /* Setup the default SPI priorities doing four at a time */
    for (index = MIN_SPI_ID; index < num_ints; index += 4)
        gicd_write_ipriorityr(gicd_base,
                      index,
                      GICD_IPRIORITYR_DEF_VAL);

    /* Treat all SPIs as level triggered by default, 16 at a time */
    for (index = MIN_SPI_ID; index < num_ints; index += 16)
        gicd_write_icfgr(gicd_base, index, 0);
}

/*******************************************************************************
 * Helper function to configure secure G0 SPIs.
 ******************************************************************************/
void gicv2_secure_spis_configure(uintptr_t gicd_base,
                     unsigned int num_ints,
                     const unsigned int *sec_intr_list)
{
    unsigned int index, irq_num;

    /* If `num_ints` is not 0, ensure that `sec_intr_list` is not NULL */
    assert(num_ints ? (uintptr_t)sec_intr_list : 1);

    for (index = 0; index < num_ints; index++) {
        irq_num = sec_intr_list[index];
        if (irq_num >= MIN_SPI_ID) {
            /* Configure this interrupt as a secure interrupt */
            gicd_clr_igroupr(gicd_base, irq_num);

            /* Set the priority of this interrupt */
            gicd_set_ipriorityr(gicd_base,
                          irq_num,
                          GIC_HIGHEST_SEC_PRIORITY);

            /* Target the secure interrupts to primary CPU */
            gicd_set_itargetsr(gicd_base, irq_num,
                    gicv2_get_cpuif_id(gicd_base));

            /* Enable this interrupt */
            gicd_set_isenabler(gicd_base, irq_num);
        }
    }

}

/*******************************************************************************
 * Helper function to configure secure G0 SGIs and PPIs.
 ******************************************************************************/
void gicv2_secure_ppi_sgi_setup(uintptr_t gicd_base,
                    unsigned int num_ints,
                    const unsigned int *sec_intr_list)
{
    unsigned int index, irq_num, sec_ppi_sgi_mask = 0;

    /* If `num_ints` is not 0, ensure that `sec_intr_list` is not NULL */
    assert(num_ints ? (uintptr_t)sec_intr_list : 1);

    /*
     * Disable all SGIs (imp. def.)/PPIs before configuring them. This is a
     * more scalable approach as it avoids clearing the enable bits in the
     * GICD_CTLR.
     */
    gicd_write_icenabler(gicd_base, 0, ~0);

    /* Setup the default PPI/SGI priorities doing four at a time */
    for (index = 0; index < MIN_SPI_ID; index += 4)
        gicd_write_ipriorityr(gicd_base,
                      index,
                      GICD_IPRIORITYR_DEF_VAL);

    for (index = 0; index < num_ints; index++) {
        irq_num = sec_intr_list[index];
        if (irq_num < MIN_SPI_ID) {
            /* We have an SGI or a PPI. They are Group0 at reset */
            sec_ppi_sgi_mask |= 1U << irq_num;

            /* Set the priority of this interrupt */
            gicd_set_ipriorityr(gicd_base,
                        irq_num,
                        GIC_HIGHEST_SEC_PRIORITY);
        }
    }

    /*
     * Invert the bitmask to create a mask for non-secure PPIs and
     * SGIs. Program the GICD_IGROUPR0 with this bit mask.
     */
    gicd_write_igroupr(gicd_base, 0, ~sec_ppi_sgi_mask);

    /* Enable the Group 0 SGIs and PPIs */
    gicd_write_isenabler(gicd_base, 0, sec_ppi_sgi_mask);
}
